Ignition magneto



Sept. 27, 1938- if u. QUINTAVALLE IGNITION MAGNETO Filed Sept. 1, 1936 Fig.

Fig.2

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Patented Sept. 27, was 2,131,523

UNITED STATES PATENT OFFICE IGNITION MAGNETO Umberto Quintavalle, Milan, Italy, assignor to Fabrica Italiana Magneti Marelli Soc. AIL, Milan, Italy, a corporation of Italy Application September 1, 1936, Serial No. 98,984

. In Italy September 20, 1935 Claims. (Cl. 171-209) The present invention relates to ignition magtop stator pole-members 2, 2' respectively, while netos particularly for internal combustion enthe lower stator pole-members 2a, 2a are simigines and has for its object a. structure for the larly connected with arms 5, 5' by means of l magnetic path in said magnetos which reduces bridges l2 and I 2'.

to a minimum the size of the parts and provides Figs. 2-4 illustrate an actual embodiment of 5 for a very high efficiency while the arrangement the above described structure; in Figs. 2-4, I deof the several members of said structure secures notes the rotary magnet inductor which extends a full separation of the mechanically operative in register with a longitudinal portion of the parts from the electric parts to impart a very stator pole members 2, 2, 2a, 2a as hereinafter high safety of operation in spite of most adverse described and is fast to a shaft 9 mounted to in conditions of use. rotate in the magneto casing II by means of In the structure of this invention the core antifriction bearings l0,said shaft extending parcarrying the windings in which current is inallel to said pole members and substantially along duced by effect of the movement of a magnet the centre line of the space enclosed therebeinductor with respect to pole shoes connected tween. with said core, has each of its ends connected The stator includes said two pairs of parallel with an arm extending therefrom and in turn laminated pole members 2, 2, 2a, 2a encircling each of these arms has extensions providing pole the space where the magnet rotor l rotated, and faces having the same sign or polarity for 00- side arms 5, 5 which are connected with respecoperation with pole shoes or faces of the magtive ends of core 4 of coil 3 and with top ones 20 net inductor, the arrangement being such that 2, 2 of said pole members.

in the respective revolution of the inductor and. Said top pole members 2, 2' extend in the dicoil carrying structure all the pole faces having rection of the axis of rotation of shaft 9 through the same sign of said inductor are at the same some extent beyond the extension of the magtime in register with cooperating pole faces of net inductor I in said direction, and in such ex- 26 the said coil structure as essential to secure a tended portions of pole members 2, 2' each of high emciency. them has a bridge l2, l2 fastened thereon, the

By the above outlined arrangement the coil opposite end of bridges l2, l2 connecting with may be easily located in any preferred position the respective lower pole members 2a, 2a which 30 with respect to mechanically operative memprovide opposite pole faces having the same sign 30 bars of the magneto and may be entirely sep- (Figs. 2 and 4). arated therefrom. The lower pole members 2a, 2a are thus con- On the annexed drawing a construction in nected with core arms 5, 5 by means of said accordance with this invention is illustrated by bridges I2, i2 and top pole members 2, 2,

way of example as embodied in a magneto havall the pole members of the same sign being thus 35 ing a structure provided with four pole faces connected with the same respective core arm 5, and an inductor comprising a four arm star- 5 and end of core 4. shaped permanent magnet, and: Said bridges I2, I2 consist of laminated mem- Figure 1 is a perspective diagrammatical view bers; they cross with each other in the space con showing the respective position of the several fined by the pole members 2, 2', 2a, 2a and they 40 parts; have holes for the location of shaft 9 there- Fig. 2 is a fragmentary longitudinal section through.

of a magneto built up in the above stated man- Of course the present invention is not rener; stricted to described and illustrated arrangement Fig. 3 is a transverse section of the magneto and includes all equivalent arrangements within 45 shown in Fig. 2 on line 3--3 of Fig. 2; the spirit of appended claims; more particularly Fig. 4 is a transverse section of said magnet the magneto may include a larger number of on line 44 of Fig. 2; pole members the number of bridges l2, [2' be In Fig. 1, i denotes a four-pole magnet inducing then larger than two, such number being in tor mounted to rotate in a stator which includes any case one half the number of pole members. 50

two pairs of poles having the same sign such What I claim as my invention and desire to sepole pairs being referenced 2, 2a and 2, 2a; cure by U. S. Letters Patent is: 3 is the coil in which current is induced and said 1. In an ignition magneto having a rotor with coil has a core 4 from whose ends two arms 5, 5 pole faces and a stator including pole faces loextend, such arms being directly connected with cated around the path of said rotor pole faces in 56 positions to be confronted in pairs by pairs of pole faces of said rotor; pole bar members extending along and located around the axis of rotation of said rotor and providing said stator pole faces, bridges transverse to said axis and each interconnecting in a set said pole bar members whose pole faces are.confronted simultaneously by pole faces of said rotor having one polarity, a core outside of the space enclosed by said pole bar members, means connecting each one of said pole bar member sets with one end of said core, and a winding on said core.

2. In an ignition magneto having a rotor with pole faces and a stator including pole faces located around the path of said rotor pole faces in positions to be confronted in pairs by pairs of pole faces of said rotor; pole bar members extending parallel with and located around the axis of rotation of said rotor and providing said stator pole faces, bridges transverse to said axis and each interconnecting in a set said pole bar members whose pole faces are faced at the same time by pole faces of said rotor having one polarity, a core extending transverse to said rotor axis and pole bar members, parts each connecting one of said pole bar member sets with one end of said core, and a winding on said core.

3. In an ignition magneto having a rotor with pole faces and a stator including pole faces 10- cated around the path of said rotor pole faces in positions to be confronted in pairs by pairs of pole faces of said rotor, pole bar members extending parallel with and located around the axis of rotation of said rotor said members confining a space intermediate them for location of said rotor and providing said pole stator faces in said space, bridges transverse to said axis and located beyond one end of said space, each of said bridges interconnecting in a set said pole bar members whose pole faces are faced at the same time by pole faces of said rotor having one polarity, a core outside of the space enclosed by said pole bar members, parts each connecting one of said pole bar member sets with one end of said core and a winding on said core.

4. In an ignition magneto having a rotor with pole faces and a stator including pole faces located around the path of said rotor pole faces in positions to be faced in pairs by pairs of pole faces of said rotor, pole bar members extending parallel with and located around the axis of rotation of said rotor and providing said stator pole faces, bridges transverse to said axis and each interconnecting in a set said pole bar members whose pole faces are faced at the same time by pole faces of said rotor having one polarity, two arms each extending from and transverse to a pole bar member of each of said sets, a core having its ends connected with said arms and a winding on said core.

5. In an ignition magneto having a rotor with pole faces and a stator including pole faces located around the path of said rotor pole faces in positions to be faced in pairs by pairs of pole faces of same rotor, pairs of pole bar members extending parallel with and located around the axis of rotation of said rotor and providing said stator pole faces said members of each pair having their said pole faces in positions to be faced at the same time by pole faces of said rotor having one polarity, bridges transverse to said axis and each interconnecting the pole bar members of each of said pairs, an arm extending from and transverse to a pole bar member of one of said pairs, a second arm extending from and transverse to a pole bar member of another one of said pairs, a core having its ends connected each with the end of one of said arms and a winding on said core.

" UMBERTO QUINTAVALLE. 

